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I defined a partial and put an observe_field in this partial, but it
doesn't invoke the action when the field changed, this is the code:
<td>
<%=select_tag 'project_version',
options_for_select(@project_versions)%>
<%= observe_field :project_version, :update=>'view_name',
:url=>{:action=>'update_view_name'},
:with=>"'project_selection='+$('project_selection').getValue()+'&project_version='+encodeURIComponent(value)"%>
</td>
<td id="view_name"><%= render(:partial=>'view_name',:layout=>false)
%></td>